It's a generalization, but it's absolutely true. So rather then putting an exhaustive list, which would be absolute the next day (because new phones come on the market every day), we give people a few words, which are generalizations.

In general, modems will work because they have to in order to call themselves modems. In general Sony Ericsson support of ETSI standard is awesome, and in general Nokia support is terrible. Siemens also seems quite good. Motorola is touch and go. iPhone will work outside the USA but not inside, because the mobile providers in the USA don't want you using the phone for anything but being a phone. Same goes with Android.

Also, as noted on that page, there's a really cheap and easy solution. Zoom model 4595, 4596 and 4598 modems are available from Amazon.com for as little as $50. It took everybody more than $50 worth of time just to read these posts, so that's the easy answer...